The present invention relates to a method of constructing a large elongate internal structure surrounded by an external structure, the internal structure being a fluid-confining structure intended to form at least part of a fluid supply plant.
The invention applies more particularly to the construction of air-distillation columns, whose height may be as much as 60 meters, surrounded by their support frameworks.
On a production site, such a column, the verticality of which must be perfect in order to ensure that the distillation process is carried out properly, is surrounded by a framework which supports the column and all or some of its items of equipment, the framework being covered with external protective metal sheeting.
In the case of large distillation columns, i.e. the size of which does not allow them to be transported, the column and its framework have hitherto been constructed or delivered separately on site and then all or part of the framework, into which the column is subsequently inserted, is erected. Such a method of construction is complex and poses many problems when assembling the framework, the column and its items of equipment, especially in order to meet the verticality constraint imposed on the column.
Such a method of construction also poses problems of safety, in particular because of the heights at which workers may be required to operate.